Bovine respiratory disease (BRD) has been one of the leading causes of economic loss to both the dairy and beef industries throughout the world. Excessive mortality, reduced weight gains, and the cost of treatment and prevention have placed a heavy burden on the industry. For years, antimicrobial therapy has been the mainstay of BRD therapy. There are many effective antimicrobial agents currently available for the treatment of BRD e.g. Nuflor®, an injectable formulation of the broad-spectrum antibiotic florfenicol.
European patent No. 546018 discloses an injectable composition of florfenicol comprising 10 to 50% by weight of florfenicol; 10 to 65% by weight of a pyrrolidone solvent; 5 to 15% by weight of a viscosity reducing agent; and 5 to 40% by weight of polyethylene glycol. This formulation is however difficult to administer, especially under cold whether conditions because the viscosity of the formulation becomes too high causing this poor syringeability.
International patent application No. WO 92/04016 discloses a composition of florfenicol in a solvent system consisting essentially of aprotic polar solvents, e.g., N-methyl-2-pyrrolidone or 2-pyrrolidone.
International patent application No. WO 2004/014340 discloses a composition of 20% florfenicol in a solvent system comprising a mixture of a hydrophilic and a lipophilic solvent, e.g. laurocapram, a skin-penetration enhancer.
United States patent application No. US 2004/0242546 disclose compositions of florfenicol comprising triacetin, dimethylamide and/or combinations thereof as a carrier.